1. Field of the Invention
The present invention relates to a heating system of a batch type reaction chamber and a method thereof, and more particularly to a heating system of a batch type reaction chamber and a method thereof, in that a heating group having a plurality of heaters for forming divided heating areas of a process space at right angles and having a pair of heating units as a heating element connected to each supplying line through separate thermostats is provided, so that each heat unit has different height and caloric value at right angles according to the divided areas, whereby it can control an uniform temperature incline of the entire process space of the reaction chamber.
2. Description of the Prior Art
Generally, a semiconductor manufacturing process or a LCD and a PDP manufacturing process includes a plurality of heat treatment process. For example, the heat treatment process as a unit process is contained in a thin-film deposition process, an activation process or a crystallization process.
In the CVD (Chemical Vapor Deposition) process, an aerial chemical compound is reacted on a heated surface of the basic material to deposit a product on the surface of the basic material. Especially, the process is very important to the production process such as a flat board display substrate (for example, LCD, PDP and so on).
FIG. 1 illustrates a semiconductor manufacturing device for depositing a silicon film on the semiconductor substrate as a CVD (Chemical Vapor Deposition) device. That is, FIG. 1 illustrates a batch type process device for treating a plurality of substrates.
The minute structure and growth result of the thin film is determined by the nucleation process and the surface diffusion on the growth interface. Also, they are influenced by the temperature of the substrate, the pressure of the reactor and the gas composition. Moreover, the change of the minute structure is generated owing to the heat treatment or the following process. Here, the change has a direct impact on the characteristic of the thin film.
As shown in FIG. 1A, the semiconductor manufacturing device includes a reaction chamber 1 for providing a process space, a heater 2 for producing an environment of a heat treatment in the reaction chamber 1, and a gas supplying device (not shown) for supplying a source gas as the material of the thin film. Here, a gas line 7 is connected to the reaction chamber 1.
Also, the semiconductor manufacturing device includes a gas discharging device for discharging a corrosive gas or a poisonous gas contained in a cold trap or scrubber and so on and a transferring device for maintaining a cleanness of the process.
Moreover, as shown in FIG. 1B, a batch type boat 3 for mounting the plurality of semiconductor substrate 100 includes a lifting device 4 for putting it into the reaction chamber 1 and an end-effector 5 for loading and unloading the semiconductor substrates 100.
In the meantime, the heating apparatus 2 for producing the environment of a heat treatment in the reaction chamber 1 is provided. In order to treat the plurality of the semiconductor substrate putted into the batch type reaction chamber in the type of resistance heating, a heater 6 of a coil type is mainly used.
In the heating apparatus 2 of the batch type, the heating area is divided into upper and lower ones, which are separately controlled and driven by sects. Also, the generation of heat is performed through a temperature controller (not shown) by stages.
In the meantime, in the conventional heating apparatus, the heat treatment processes are performed in one reaction chamber under the different environments in temperature in order to promptly treat each process. Accordingly, it is necessary to improve the productivity thereof through sudden rise and fall in temperature and control the supply of an unnecessary calory for maintaining the characteristics of the semiconductor element. For this reason, the heating apparatus for rising and falling the temperature at high speed has been demanded so as to minimize an over-head time necessary to reach the temperature of each process.
That is, the reason is that the semiconductor process includes a plurality of heat treatment processes and the reduction of the process time is essential to maximize the productivity thereof.
However, in the conventional heating apparatus of the resistance heating type, there is a problem in that the process time is delayed in heat treatment.
That is, quite a time is required to increase the temperature of the heat treatment on account of the property of matter of the heating coil itself, thereby the process is delayed. Also, since the heating coil is surrounded by an adiabatic body (an adiabatic block 8), quite a time is required to cool it after the completion of the process.
Accordingly, on account of the delay of each process, the entire process is also, delayed, thereby leading to the lowering of the productivity thereof.
For this reason, a RTP device of a single wafer type for rising and falling the temperature at high speed used in the batch type process has been demanded. In this case, a graphite, a MoSi2 (a kanthal super), a silicon carbide and so on can be used as the heating resistance body. However, it is difficulty to form the coil shape such as the electronic heater owing to the forming characteristics thereof. Accordingly, as shown in FIG. 1C, a plurality of pole type heaters 9 is vertically and separately formed along the outer circumference of the reaction chamber 1.
However, in the conventional RTP device, there are problems in it is difficulty to minutely control the process temperature and cannot cope with the various environment in heat treatment.
For example, since the pyrolysis temperature of the source gas and the temperature of the semiconductor substrate have a strong impact on the deposition speed and the particle producing speed as well as the composition and minute organization of the product, it is necessary to minutely control the temperature of the heating apparatus.
That is, in the above heat treatment processes, it is necessary to produce a uniform temperature over the entire space of the reaction chamber. Here, the heat of the heating apparatus 2 is transmitted to the interior of the reaction chamber 1 through a radiation. Meanwhile, in the inside of the reaction chamber, the heat is transmitted through the radiation and convection.
Here, because the process space of the batch type is several tens times as large as that of the single wafer type in volume, in order to control a uniform temperature incline of the entire process space of the reaction chamber 1 through the heating apparatus, it is necessary to vertically control the temperature of the process space by sects.
Generally, the temperature of the upper portion of the reaction chamber 1 is higher than that of lower portion thereof owing to the convection. Accordingly, in order to control a uniform temperature incline of the entire process space of the reaction chamber 1, it is necessary to heat the upper portion thereof lowly in comparison with the lower portion. Actually, in the electronic heater of the coil type, the heating units as the heat coil divided into upper and lower portions are separately controlled in order to produce the uniform temperature of the entire process space.
However, in the conventional heating unit for the RTP, since the plurality of the heating units of the linear pole type is vertically formed, it is difficulty to produce different temperatures by sects. Also, there is a problem in that it can bring about a badness thereof in the plurality of unit processes for a heat treatment.